1. Field of the Invention
The present invention relates to a climbing safety device for a tower crane, and more particularly to a climbing safety device for a tower crane which can immediately cope with an accident of an operator falling off a ladder of the tower crane, caused by a slip of the operator or a sudden change of weather conditions occurring when the operator climbs up or down the ladder, thereby protecting the operator's life.
2. Description of the Related Art
When a high-rise and large-scale building is constructed, a tower crane is generally used to carry construction materials to upper stories. As shown in FIG. 4, such a tower crane, which is denoted by the reference numeral 90, includes a mast 91 installed on a foundation to extend vertically, a horizontal box frame, that is, a jib 93, mounted to an upper end of the mast 91, and provided with a counterweight 92 so as to be maintained in a horizontal state, a turntable 94 mounted to an upper portion of the mast 91, and adapted to rotate the jib 93 left and right in accordance with rotation of a swing motor equipped therein, and an operator cab 95 installed on the turntable 94. In order to allow an operator to access the operator cab 95, a vertical ladder 96 is installed within the mast 91.
When the operator desires to access the operator cab 95 in order to operate the tower crane, he climbs up the vertical ladder 96 to enter the operator cab 95. After completion of desired tower crane operations, the operator climbs down the vertical ladder 96. In order to cope with an unexpected accident of the operator occurring during the climbing, a safety rope (not shown) is provided.
However, such a safety rope cannot secure a desired safety for protecting the operator's life when the operator falls off the ladder due to his slip, a sudden change of weather conditions in the winter season or rainy season, or strong wind, because it depends from the operator cab 95 to the foundation, and its lower end is simply firmly held on the body of the operator.